Code responsive systems



Oct. 13, 1964 R. J. BYRNEs E'rAL 3,152,681

' com: RESPONSIVE SYSTEMSv Filed May 25. 1961 4 Sheets-Sheet l CONVES/OE Laax/El 6 Oci- 13 1964 R. J. BYRNEs ETAL 3,152,681

CODE RESPONSIVE SYSTEMS Oct. 13, 1964 R. J. BYRNr-:s ETAL. 3,152,681

coni: RESPONSIVE sysfrEMs Filed May 25, 1961 4 sheets-sheet s L cc L2 3oI I 32 8 9 l 1/ 7 a .VA'AVAV I *'{A'A' I 34 L T5 36 G, H9 Eff D I 7 Ocf-13 1964 R..J.-BYRNEs ETAL y 3,152,681

conE RESPONSIVE SYSTEMS Filed May 25, 1961 4 Sheets-Sheet 4 Q. 6 L] cc/L2 /O COMMON 'en o IVO, 2

United States Patent() 3,152,681 CODE RESPONSIVE SYSTEMS Richard J.Byrnes, West Allis, James T. Pence, Milwaukee, and Barney O. Rae,Shorewood, Wis., assignors to Cutler-Hammer, Inc., Milwaukee, Wis., acorporation of Delaware Filed May 25, 1961, Ser. No. 112,707 8 Claims.(Cl. 198-38) This invention relates to code responsive systems and moreparticularly to control systems which respond to control signals fromcode responsive moving-article detectors and control the routing of thearticles.

While not limited thereto, the invention is especially applicable toconveyor systems and the like for controlling the routing of articles orarticle carriers.

William D. Brand and Harold S. Montgomery copending application SerialNo. 8,628, filed February l5, 1960, now Patent No. 3,034,634, issued Mayl5, 1962, relates to a coded card controlled system for controlling therouting of articles or article carriers and employs a contact lingertype detecting and identifying device. This invention relates toimprovements thereover and more particularly relates to control systemsof the universal type which are usable with either contact finger typecode detectors or with proximity type code detectors or combinationsthereof.

An object of the invention is to provide improved code responsivesystems.

A more specitic object of the invention is to provide improved controlsystems operable with and responsive to diverse types of code sensingdevices.

Another specific object of the invention is to provide improved routingcontrol systems which are arranged to reduce to a minimum themisdirection of articles in the event of failure and reestablishment ofthe system power supply.

Another specific object of the invention is to provide improved routingcontrol systems which are arranged so that it is impossible for anarticle destined for one station to be diverted to a preceding station.

Another object of the invention is to provide improved routing controlsystems having or logic code functions to render the same responsive toeither one of two coded article detector signals.

Another object of the invention is to provide improved routing controlsystems having and logic code functions to render the same responsive totwo simultaneously occurring coded article detector signals.

Another object of the invention is to provide improved routing controlsystems having a plurality of groups of article detecting devices for arespective plurality of routn ing control circuits wherein one of thearticle detecting devices is common to the plurality of groups thereof.

A further specific object of the invention is to provide improvedtransistor controlled routing control systems operable immediately afterinitiating the diverting of an article to reset into readiness forcontrolling the diverting of another article.

Other objects and advantages of the invention will hereinafter appear.

According to the invention, there are provided article routing controlsystems for automatically routing articles traveling along a mainconveyor to predetermined destination branch conveyors in accordancewith predetermined codes carried by such articles. Articles or articlecarriers such as trays or the like carry code-bearing cards which may beof the contact bridging type or may have electrically conductingelements thereon in coded positions for activating proximity detectingdevices. A card reader is mounted at the side of the main conveyor forreading the codes on the cards. The card reader may have contact fingersfor sensing the coded cards or may have proximity probe devices fordetecting the passage of coded conducting members thereby. Controlcircuits readily connectable to either of the aforementioned types ofreaders are provided for storing the read code until the articleapproaches its destination branch conveyor. At this point, the articleoperates ya switch to utilize the stored code to operate a diverter toturn and divert the article to the destination branch conveyor and tooperate the branch conveyor to move such article away from the divertingjunction. Another switch on the branch conveyor is engaged by thearticle to restore the system to normal condition and to stop the branchconveyor. The system is constructed and arranged so that it isphysically impossible to divert an article intended for a succeedingbranch conveyor to a preceding branch conveyor and to reduce to aminimum the misdirection of articles in the event of system powerfailure.

The above mentioned and other objects and advantages of the inventionand the manner of obtaining them will best be understood by reference tothe following detailed description of exemplary embodiments of routingcontrol systems taken in .conjunction with the accompanying drawings,wherein:

FIGURE 1 is a top view of an article conveyor and diverter controlsystem constructed in accordance with the invention;

FIG. 2 is a circuit diagram of a diverter control system operable by asingle proximity detector device to control diversion of articles from amain conveyor to a branch conveyor;

FIG. 3 is a .circuit diagram of a diverter control system having an andlogic circuit operable in response to simultaneous signals from twoproximity detector devices.

FIG. 3a is a simplified illustration of the circuit of FIG. 3;

FIG. 4 is a circuit diagram of a diverter control system having an orlogic circuit operable in response to either one of two proximitydetector devices;

FIG. 4a is a simplified illustration of the circuit of FIG. 4;

FIG. 5 is a circuit diagram of a diverter control system having an orlogic circuit operable in response to either one of two contact lingerdetector devices;

FIG. 6 is a circuit diagram of a routing control system having threeproximity detector devices for controlling two diverter control systems;

FIG. 6a is a simplified illustration of the system of FIG. 6; and

FIG. 7 is a circuit diagram of a routing control system having threecontact fingers for controlling two diverter control systems.

Referring to FIG. l, for illustrative purposes, there is shown a mainconveyor 2 having a pair of branch conveyors 4 and 6 extending laterallyin parallel relation or the like from one side of the main conveyor.Diverter mechanisms 8 and 10 are mounted at the junctions between mainconveyor 2 and the respective branch conveyors 4 and 6. Each suchdiverter mechanism is operable when actuated to its diverting positionshown in dotted lines to turn and divert an article or article carriersuch as tray 12 or the like onto the associated branch conveyor. Thesediverter mechanisms are operated into their diverting positions bysuitable means such as iluid means or electromagnetic means havingoperators such as solenoids or the like and are spring returned to theirnormal non-diverting positions. Each such diverter mechanism comprisesthe aforementioned electromagnetic operator mounted at the side of mainconveyor 2 and a row of skate wheels or the like for diverting articles.

For a more detailed disclosure of the diverter mechanism, reference maybe had to Richard I. Byrnes, Robert N. Eck, Clyde F. Robbins and NorbertSadowski copending application Serial No. 37,611 led June 2l, 1960 nowPatent No. 3,058,567, dated October 16, 1962.

A code reader 14 is mounted at one side of main conveyor 2 ahead of thefirst diverter mechanism 8. The function of the `code reader is todetect and identify the code on a card 16l1eld in a slot in the side oftray 12 and to control diversion of the tray to its predetermined branchconveyor destination. While a card 16 is shown for exemplary purposes,the code can be applied by other means to an article or article carrier.Card 16 may be of the laminated type having an electrically conductinginner layer and electrically insulating outer layers. The insulatinglayer exposed to the code reader is provided with a plurality of cut-outportions in coded positions to expose the conducting layer to engagementby contact fingers mounted on the code reader whereby to electricallyconnect the contact fingers to one another. For a more detaileddescription of the contact finger type code reader and laminated card,reference may be had to the aforementioned William D. Brand and HaroldS. Montgomery `copending application.

Alternatively, code reader 14 may be of the proximity switch typecomprising a plurality of detector members or proximity probes extendingtherefrom a short distance over the side of the main conveyor. Tooperate the proximity probes, card 16 is provided in predetermined codedlocations thereon with metallic elements of electrically conductingmaterial such as copper or the like. When a coded article passes thereader such that the conducting elements match the positions of theprobes on the reader, a control is initiated to divert the tray to itspre-determined branch conveyor destination. For a more detaileddescription of the proximity probe, reference may be had to Richard I.Byrnes, Walther Richter, Robert W.y Spink and Merle R. Swinehartcopending application Serial No. 112,716, filed May 25, 1961.

Limit switches LS1 and LS2 are mounted on main conveyor 2 immediatelyahead of the respective diverter mechanisms 8 and 10. The function ofeach such limit switch when operated by a moving tray is to causeactuation of the associated diverter mechanism into its divertingposition provided the .code reader has indicated that the associatedbranch conveyor is its correct destination. Limitfswitches LS1 and LS2provide gating for proper diverter operation such that article carriersin close proximity with each other are not misdirected. Anotherfunctionof each such limit switch is to start operation of theassociated branch conveyor.

Limit switches LS3 and LS4 are mounted on the respective branchconveyors 4 and 6 at least one tray length from the main conveyor. Thefunction of each such limit switch when operated by a diverted tray isto restore the associated control circuit to normal condition and tomaintain operationl of the associated branch conveyor until the divertedtray has cleared such limit switch.

Referring to FIG. 2, there is shown a control circuit enclosed in brokenlines and indicated generally as CC. Control circuit CC is supplied withalternating current power through power supply lines L1 and L2 and isprovided with four terminals a, b, c and d adapted for connecting a codediscriminating device of a selected type thereto as hereinafterdescribed.

The code discriminating device shown in FIG. 2 comprises a proximityprobe PP enclosed in broken lines and provided with terminals A, B, C, Dand E adapted for connecting the same in a variety of ways to one ormore control circuits CC and to other proximity probes as hereinaftermore fully described. A portion of the circuit of proximity probe PP isshown in FIG. 2. The reference `characters identifying the elements ofthe proximity probe :are similar to those employed in the aforementionedRichard J. Byrnes, Robert W. Spink, Walther Richter and Merle R.Swinehart application. Proximity probe PP comprises a transistor T4having an emitter-base junction E-B which is normally controlled toeffect current flow through emitter-collector junction E-C thereof. Thetransistor is supplied with unidirectional voltage from terminals A andE so that the current flowing through the transistor also flows throughresistor R7 in series. Terminals B, C and D are output control terminalsand terminal B is utilized in the connection shown in FIG. 2. Whentransistor T4 conducts, it effectively shunts terminals A and B totransmit a first control to control circuit CC. When the proximity probesenses conducting material, transistor T4 is rendered non-conducting totransmit a second control to control circuit CC as hereinafter morefully described.

Control circuit CC is provided with low voltage means which responds tothe `control received from the proximity probe to initiate a furthercontrol function. This low voltage means comprises a transistoramplifier AMP enclosed in broken lines and a low voltage relay LVRconnected to the output of the amplifier. The low voltage circuit issupplied with power from a transformer TR having its primary windingconnected across lines L1 and L2. The secondary winding of transformerTR is connected to alternating current supply terminals 18 and 20 ofamplifier AMP. The amplifier is of the static type which is adapted forpotting in thermo-setting material and is provided externally thereofwith control terminals 22, 24 and 26 and an additional terminal 28.Terminal 28 and terminal 2i) constitute unidirectional current outputterminals for the amplifier.

Amplifier AMP is provided with a rectifier circuit for providingunidirectional voltage to a transistor T5. This rectifier circuitcomprises a unidirectional diode RTS connected from terminal 18 toemitter E of transistor T5, collector C of the transistor being`connected to output terminal 28. Amplifier AMP is provided with afilter circuit for filtering the rectified voltage. This filter circuitcomprises a capacitor C1 connected from the junction of diode RTS andemitter E to output terminal 20 and a pair of voltage divider resistorsRS and R9 connected in series across capacitor C1. The junction ofresistors R8 and R9 is connected to amplifier terminal 22 andtherethrough to terminal a of control circuit CC. Emitter E oftransistor T5 is connected to amplifier terminal 24 and therethrough toterminal b of control circuit CC. Base B of transistor T5 is connectedto amplifier terminal 26 and therethrough to terminal c of controlcircuit CC. A control resistor R10 is connected between emitter E andbase B of transistor T5. The operating coil of relay LVR is connectedacross output terminals 28 and 20 of the amplifier. A unidirectionaldiode RT6 is connected across output terminals 2t) and 28 to provide adischarge path for the induced voltage of the operating coil of relayLVR.

Control circuit CC is also provided with means for maintaining relay LVRenergized after the input control to amplifier AMP terminates. Thismeans comprises a maintaining circuit for the operating coil of relayLVR in shunt of amplifier AMP and extending from terminal 24 through anormally closed contact 1 of a control relay CR and a normally opencontact 1 of relay LVR to terminal 28.

There is also provided in control circuit CC means for storing the inputcontrol signal until it is utilized when the tray reaches the divertingdevice associated with the destination branch conveyor. This meanscomprises control relay CR and circuits therefor. Relay CR is providedwith an operating circuit extending from line L1 through a normallyclosed contact 1 of limit switch LS1, a normally open contact 2 of relayLVR and the operating coil of relay CR to line L2. -Relay CR is alsoprovided with a self-maintaining circuit extending from line L1 througha normally open contact 2 of relay CR, a normally closed contact 1 of arelay DCB and the operating coil of relay CR to line L2.

Control circuit CC is also provided with means responsive to a movingarticle leaving the code reader for controlling routing of the articleto the destination indicated by the code reader. This means comprises apair of diverter control relays DCA and DCB and circuits therefor andlimit switch LS1. Relay DCA is provided with an operating circuitextending from line L1 through contact 2 of relay CR, a normally openycontact 2 of limit switch LS1 and the operating coil of relay DCA toline L2. Relay DCA is also provided with a self-maintaining circuitextending through a normally open contact 1 thereof in shunt of contact2 of relay CR. Relay DCB is provided with an operating circuit extendingfrom line L1 through contact 2 of relay CR, contact 2 of limit switchLS1, a normally open contact 2 of relay DCA and the operating coil ofrelay DCB to line L2. A counter CTR is connected for energization inparallel with the operating coil of relay DCA for registering the numberof articles assigned by the code reader to the branch conveyordestination. A diverter DIV is connected for energization through anormally open contact 3 of relay DCB across lines L1 and L2.

Control circuit CC is further provided with means under the control ofthe aforementioned routing control means for controlling operation ofthe branch conveyor. This means comprises a branch conveyor controlrelay CCR, a motor forward contactor F, a branch conveyor motor BCM,limit switch LS3 and circuits therefor. Relay CCR is provided with anoperating circuit extending from line L1 through contact 1 of relay DCA,a normally open contact 2 of relay DCB and the operating coil of relayCCR to line 2. A self-maintaining circuit extends from line L1 through anormally closed contact 1 of limit switch LS3, a normally open contact 1of relay CCR and the operating coil of relay CCR to line L2. Forwardcontactor F is provided with an operating circuit extending from line L1through a normally closed stop switch ST, a normally open contact 3 ofrelay CCR, a normally closed contact 2 of a reverse contactor R and theoperating coil of forward contactor F to line L2. A maintaining circuitfor contactor F extends through a normally open Contact 2 of limitswitch LS3 in shunt of contact 3 of relay CCR.

There are also provided manual means for operating motor BCM comprisinga motor forward operating control manual switch FOR connected in shuntof contact 3 of relay CCR for operating forward contactor Findependently of relay CCR and limit switch LS3.

A reverse contactor R is provided for operating motor BCM in the reversedirection. Contactor R is provided with an operating circuit extendingfrom line L1 through stop switch ST, a normally closed contact 2 ofrelay CCR, a manual reverse switch REV, the operating coil o contactor Rand a normally closed contact 1 of contactor F to line L2. Aself-maintaining circuit for contactor R extends through its normallyopen contact 1 in shunt of manual switch REV.

The operation of the system of FIG. 2 will now be described. A reducedvoltage is applied by transformer TR to amplier AMP. This voltage isrectified by diode RTS and filtered by the filter network comprisingcapac itor C1 and resistors R3 and R9. The resulting lteredunidirectional voltage is applied across the emitter-col lector junctionof transistor T 5 and the operating coil of relay LVR in series.Normally relay LVR remains deenergized because transistor T5 does notconduct. This is for the reason that the base voltage of transistorTS isat the same level as the emitter voltage thereof. Normally current flowsfrom the left-hand end of the secondary winding of transformer TRthrough terminal 1S, diode RTS, terminals 24, b :and A, theemitter-collector junction of transistor T4, resistor R7 and terminalsE, d and 20 to the right-hand end of the secondary winding oftransformer TR. As a result, transistor T4 functions in effect as aclosed switch and shunts resistor R10 and diode RT3. Consequently,transistor T5 remains nonconducting. As transistor T4 when conducting isnot a perfect short circuit but has a small voltage drop thereacross,diode RTS is employed in series with resistor R10. The forward voltagedrop of diode RTS is substantially equal to the voltage drop across theemitter-collector junction of transistor T4 to maintain the base voltageof transistor T5 at the same level as the emitter voltage thereof.

When proximity probe PP senses :a conducting element passing thereby,transistor T4 is momentarily rendered non-conducting and functions ineffect as an open switch to interrupt the shunt circuit across resistorR10. As a result, current ows through resistor R10 and diode RTS. Thevoltage drop across resistor R10 renders the Voltage at base B negativerelative to the voltage at emitter E of transistor T5 to cause currentflow through the emittercollector junction of transistor T5 to energizethe operating coil of relay LVR. Relay LVR closes contact 1 to maintainenergization thereof through contact 1 of relay CR after transistor T5is rendered non-conducting. As will be apparent, as soon as theconducting element passes proximity probe PP, transistor T4 is -againrendered conducting and shunts resistor R10 to render transistor T5non-conducting.

Relay LVR also closes its contact 2 to energize the operating coil ofrelay CR through contact 1 of limit switch LS1. Relay CR closes itscontact 2 to complete a self-maintaining circuit through contact 1 ofrelay DCB. Relay CR also opens its contact 1 to interrupt themaintaining circuit of relay LVR. Amplilier AMP and relay LVR are nowrestored to their normal condition into readiness to receive anotherinput signal. The input control signal that has been received is storedon relay CR until the tray which has been sensed by code reader 14 inFIG. l engages limit switch LS1.

Engagement of limit switch LS1 by the tray causes opening of contact 1land closure of contact 2 thereof. Contact 1 of limit switch LS1interrupts the original energizing circuit of relay CR .to preventregistration of another input signal thereon until the signal storedthereon has been used. Contact 2 of limit switch LS1 completes anenergizing circuit through contact 2 of rel'ay CR for relay DCA andcounter CTR in parallel. As a result, counter CTR counts the trayassigned to the branch conveyor. Relay DCA closes its contact 1 tocomplete a self-maintaining circuit in shun-t of contact 2 of relay CRand closes its contact 2 to energize relay DCB. Relay DCB opens itscontact 1 to interrupt the maintaining circuit of relay CR to causerelay CR to restore. Relay CR yrecloses contact 1 and reopens contact 2.The signal stored on relay CR has now been transferred to relays DCA andDCB. Relay DCB also closes its contact 3 to energize diverter DIV whichis similar to diverter mechanism S in FIG. 1 thereby to actuate thediverter wheels to the dotted line position. As a result, the tray isturned and diverted to the branch conveyor. Relay DCB also closes itsContact 2 to energize relay CCR through contact 1 of relay DCA. RelayCCR closes its contact 1 to complete a self-maintaining circuit throughcontact 1 of limit switch LSS. Relay CCR also opens its contact 2 toprevent energization of reverse contactor R and closes its Contact 3 toenergize forward contactor F through stop switch ST and Contact 2 ofcontactor R. Contactor F closes suitable contacts to operate motor BCMin the forward direction whereby the branch conveyor carries the traytherealong toward limit switch L83.

As isoon as the tray disengages limit switch LS1, contact 1 :thereofrecloses to render relay CR ready to store another input signal. Limitswitch LS1 also reopens contact 2 to interrupt energization of relaysDCA and DCB and counter CTR. Relay CCR, however, remains energizedthrough its maintaining circuit until the diverted tray engages limitswitch LS3.

When the tray engages limit switch LS3, contact 1 thereof opens andcontact 2 thereof closes. Contact 2 of limit switch LS3 completes anenergizing circuit for contacter F in shunt of contact 3 of relay CCR.Contact 1 of limit switch LS3 interrupts energization of relay CCR torestore the latter. As will be apparent, contact 2 of limit switch LS3maintains the branch conveyor running following restoration of relay CCRuntil the tray clears such limit switch thereby to move the tray awayfrom the diverting junction. When the tray disengages limit switch L83,contact 1 thereof recloses without effect and contact 2 thereof reopensto deenergize contacter F and stop the branch conveyor.

If it is desired to run the branch conveyor under manual control, switchFOR is pressed to energize contactor F through stop switch ST andcontact 2 of contactor R. As a result, the branch conveyor runs in theforward direction until switch FOR is released to allow it to reopen.Depression of manual switch REV energizes contacter R through stopswitch ST, contact 2 of relay CCR and contact 1 of contactor F therebyto cause motor BCM to run the branch conveyor in the reverse direction.Contacter R closes its contact 1 to complete a 'self-maintaining circuitin shunt of switch REV to maintain the branch conveyor running in thereverse direction following release of switch REV until stop switch STis pressed to stop the motor or until relay CCR is energized in responseto the routing of a tray to the branch conveyor. If the branch conveyoris running in the reverse direction when a tray is automatically beingrouted thereto, relay CCR opens its contact 2 to interrupt the circuitof contractor R and closes its contact 3 as hereinbefore described toenergize contacter F. As a result, the branch conveyor operation isautomatically changed from reverse operation to forward operation toprevent the incoming tray from jamming at the diverting junction.

Referring to FIG. 3, there is shown a diverter control circuit havingmcdied input control means. In FIG. 3, reference characters like thosein FIG. 2 have been ernployed for like parts. Control circuit CC issimilar to that in FIG. 2 and only a portion thereof has been shown indetail to avoid duplication. The modification in FIG. 3 comprises an andlogic circuit, that is, two proximity probe devices PPI and FP2 areconnected to control circuit CC iand to one another in such a mannerthat the control circuit operates only in response to a signal fromdevices PP1 and FP2. In other Words, operation of the control circuitrequires concurrent output control from both of the probe devices andthe control circuit cannot be operated by either probe device alone.

For this purpose, probe device PPI is connected to control circuit CC inthe same manner as probe device PP was connected in FIG. 2. That is,terminals A, B and E of probe device PP1 are connected directly toterminals b, c and d of the control circuit, respectively. Terminals A,B and E of probe device PP2 are also connected to terminals b, c and d,respectively. In addition, terminal D of probe device PPI is connectedto terminal D of probe device PPZ.

In FIG. 3, transistors T4 of probe devices PPI and PPZ normally conductcurrent in the manner hereinbefore described and stop conducting whenthe probe device senses conducting material adjacent to the tip of Itheprobe. Let it be assumed that probe device PPI alone senses conductingmaterial to render transistor T4 thereof non-conducting. Current iiowsfrom the positive side of the direct current source through terminal b,

terminal A and transistor T4 of probe device FP2 and then in parallelbranches to the negative side of the direct current source. One branchextends through resistor R7 and terminal E of probe device FP2 toterminal d of control circuit CC and the other branch extends throughterminal D Aof probe device PP2 and terminal D and resistor R7 andterminal E of probe device PPI to terminal d of the control circuit.This maintains resistor R10 ef -fectively shunted so that transistor T5does not respond.

8 However, if transistors T4 of both probe devices are renderednon-conducting simultaneously, the shunt across resistor Riti isinterrupted to cause control circuit CC to respond as hereinbeforedescribed.

The circuit of FIG. 3 is shown in simpliiied form in FIG. 3a whereintransistors T4 of probe devices PP1 and PPZ are represented as switchesSW1 and SW2, respectively. It will be apparent that connection ofterminals D of the probe devices together connects switches SW1 and SW2in parallel across resistor R10. Therefore, to obtain current ow throughresistor R10, it is necessary to open both switches SW1 and SW2 at thesame time.

Referring to FIG. 4, there is shown a diverter control circuit havingmodified input control means. In FIG. 4, reference characters like thosein FIG. 3 have been employed for like parts. The modification in FIG. 4cornprises an or`logic circuit, that is, two proximity probe devices PPItand PP?. are each connected to control circuit CC in the isame manneras shown in FIG. 2 and either probe device is capable of controllingcircuit CC. The modification in FIG. 4 differs from the arrangement ofFIG. 3 in that the connection between terminals D of the probe deviceshas been omitted.

The circuit of FIG. 4 is shown in simplilied form in FIG. 4a. Referringto FIG. 4a, it will be apparent that when switches SW1 and SW2corresponding to transistors T4 of probe devices PPI tand PFZ,respectively, are closed, current iiows through these switches inparallel to shunt resistor R10. If switch SW1 is opened, currentcontinues to flow from the positive side of the source through switchSW2 and resistor R7 of probe device PPZ to the negative side. However,opening of switch SW1 causes current iiow through resistor R10, diodeRTS and resistor R7 of probe device PPI to the negative side. Also, ifswitch SW2 is opened While switch SW1 remains closed, current flows fromthe positive side of the source through resistor R10 and diode RTS andresistor R7 of probe device FP2 to the negative side of the source.Diodes RT3 isolate the probe devices from one another so that eitherprobe device is capable of controlling transistor T5. Of course,concurrent opening of switches SW1 and SW2 also causes transistor T5 tobecome conducting.

Referring to FIG. 5, there is shown a diverter control circuit havingdifferent input control means. In FIG. 5, reference characters likethose in FIG. 2 have been employed for like elements. The circuit inFIG. 5 comprises an or logic circuit arrranged so that either one of twoinput control signals is capable of controlling control circuit CC.Terminals F and G of contact linger code reader 3d 'are respectivelyconnected to terminals a and c of control circuit CC to form a firstinput connection. Terminal I-I of code reader 3i) is connected toterminal G thereof so that terminal I-I forms with terminal F a secondinput connection.

Code reader 30 is similar to the code reader disclosed in theaforementioned William D. Brand and Harold S. Montgomery copendingapplication and comprises a supporting member or base 32 mountable atthe side of a conveyor lso that electrical contact fingers 34, 36 and 38extend over the conveyor. A coded card 40 is held in a slot in a tray orthe like fand is engaged by the contact lingers as the tray is conveyedpast the reader station. Card 4d may be of the laminated type or thelike having an electrically conducting inner layer and electricallyinsulating outer layers. The insulating layer exposed to the contactfingers is provided with cutout portions in coded positions to exposethe `conducting layer for engagement by the contact lingers whereby toelectrically connect two or more of the contact lingers. As will :beapparent, in the arrangement shown in FIG. 5, contact linger 34 forms acommon connection and connecting thereof either to contact linger 36 orcontact finger 38 causes operation of transistor T5.

Connection of contact fingers 34 and 36 completes a circuit frompositivevoltage through resistor R10, terminals c and G, contact finger 36, card40, contact finger 34, terminals F and a and resistor R9 to the negativeVoltage. As a result, the voltage drop across resistor R10 is applied tothe emitter-base junction to render base B negative relative to emitterE thereby to cause transistor T to conduct and energize relay LVR.Connection of contact fingers 34 and 38 completes a similar circuittherethrough to control transistor T5. Of course, connection of contactfingers 34, 36 and 33 to one another also causes transistor T5 toconduct. Comparison of FIGS. 4 and 5 will show that control circuit CCis of the universal type and is adapted to function with either theproximity probe type sensing devices of FIG. 4 or the contact lingertype sensing devices of FIG. 5.

Referring to FIG. 6, there is shown a routing control system havingthree proximity probe devices PPI, PP2 and PPC, probe device PPC beingcommon to the other two probe devices. These three probe devices areconnected for selectively controlling two control circuits CCI and CC2.In FIG. 6, reference characters like those in FIGS. `2, 3 and 4 havebeen employed for like elements.

Terminals A of probe devices PPI, PP2 and PPC are connected to oneanother and to terminals b of both control circuits CCI land CC2. Theseconnections provide positive voltage to the three probe devices inparallel and connect the positive sides of the sources to one another.Terminals E of probe devices PPI, PP2 and PPC are connected to oneanother and to terminals d of control circuits CCI and CC2. Theseconnections provide negative voltage to the three probe devices andconnect the negative sides of the sources to one another. Terminal B ofprobe device PPI is connected to terminal c of control circuit CCI as inFIGS. 2, 3 and 4. Terminal B of probe device PP2 is similarly connectedto terminal c of control circuit CC2. These connections constitutecontrol connections from probe devices PPI and PP2 to the respectivecontrol circuits CCI and CC2. Terminals C of probe devices PPI and PP2are connected to one another and to terminal D of probe device PPC.These connections render common probe device PPC operable with eitherprobe device PPI or PP2 to operate control circuit CCI or CC2. That is,when probe devices PPI and PPC sense conducting material and rendertheir transistors T4 non-conducting, control circuit CCI is operated.Similarly, probe devices PP2 and PPC operate control circuit CC2.

FIG. 6a shows the circuit of FIG. 6 in simplied form and transistors T4of the probe devices are represented therein by switches SWI, SW2 andSWC. If switch SW1 alone is opened, current continues to flow throughswitch SWC, diode RT4 and resistor R7 of probe device PPI in shunt ofresistor R of control circuti CCI so that transistor T5 of this controlcircuit remains non-conducting. Also, opening of switch SW2 has noeiiect because current fiows through switch SWC, diode RT4 has no effectbecause current ows through switch SWC, diode RT4 and resistor R7 ofprobe device PP2 in shunt of resistor R10 of control circuit CC2.However, when contacts SW1 and SWC open at the same time, current flowsthrough resistor R10 of control circuit CCI and diode RT3 and resistorR7 of probe device PPI to render transistor T5 of this control circuitconducting. Diode RT4 of probe device PP2 isolates this probe devicefrom control circuit CCI. When switches SW2 and SWC open at the sametime, current flows through resistor R10 of control circuit CC2 anddiode RT3 and resistor R7 of probe device PP2 to render transistor T5 ofcontrol circuit CC2 conducting. Diode RT4 of probe device PPI isolatesthis probe device from the control circuit CC2 so that it cannotinterfere with operation thereof. It will be apparent that probe devicePPI and common probe device PPC sense a first code to operate controlcircuit CCI which may control routing of articles to branch conveyor 4in FIG. I. Also, probe device PP2 and common probe device 10 PPC sense asecond code to operate control circuit CC2 which may control routing ofarticles to branch conveyor 6 in FIG. 1. All three probe devices may bemounted on a reader such as I4 in FIG. l to sense conducting members ona card 16 held in a slot on tray I2.

Referring to FIG. 7, there is shown a routing control system having acontact finger type code reader similar to that in FIG. 5 forselectively controlling two control circuits CCI and CC2. The system inFIG. 7 is similar to the system in FIG. 6 except that contact fingersare employed instead of proximity probe devices. In FIG. 7, referencecharacters like those in the prior figures have been employed for likeelements.

In FIG. 7, common contact finger 34 is connected from terminal F toterminals a of control circuit CCI and CC2. Contact finger 36 isconnected from terminal G to terminal c of control circuit CCI andcontact finger 38 is connected fromterminal H to terminal c of controlcircuit CC2.

When card 40 bridges or electrically connects contact fingers 34 and 36,current flows from the positive side of the source in control circuitCCI through resistor R10, terminals c and G, contact finger 36, card 40,contact finger 34, terminals F and a and resistor R9 to the negativeside of the source. Current normally flows through resistors R8 and R9so that connection of contact fingers 34 and 36 through card 40 causesthe voltage drop across resistor R8 to be applied across resistor R10 tocause current ow through the latter. As a result, the voltage dropacross resistor R10 is applied to the emitter-base junction oftransistor T5 to render transistor T5 conducting and to energize relayLVR. Relay LVR then controls the associated diverter and operates theassociated branch conveyor 4 to effect routing of an article to thelatter in the manner described in conjunction with FIG. 2.

When card 40 bridgescontact lingers 34 and 33, the voltage drop acrossresistor R8 of control circuit CC2 is applied across resistor R10therein to cause current flow through resistor R10, terminal c ofcontrol circuit CC2, terminal H of reader 30, contact finger 38, card40, contact finger 34, contact F of reader 30, terminal a of controlcircuit CC2 and resistor R9 to the negative side of the source. As aresult, transistor T5 in control circuit CC2 is rendered conducting toenergize relay LVR and to control routing of the article to branchconveyor 6 in FIG. 1.

It will be apparent that control circuit CC shown in detail in FIG. 2 isconstructed so that it may be employed with either contact finger typesensing devices or proximity type devices. A plurality of controlcircuits CC may be controlled by employing a contact finger or proximitydevice for each thereof and one additional common contact finger orproximity device. The control circuit such as CC in FIG. 2 isconstructed so that it receives a control signal when reader 14 in FIG.l senses a code and stores the signal until tray I2 engages the limitswitch LSI or LSZ associated with the branch conveyor destination of thetray.

Branch conveyors 4 and 6 are preferably spaced close to one another andbranch conveyor 4 is preferably spaced close to code reader 14 such thata single code reader can be employed to control diversion of articles totwo branch conveyors. The spacing between branch conveyors 4 and 6 andthe spacing between branch conveyor 4 and code reader I4 relative to thelength of trays 12 being conveyed is preferably such that a precedingtray cannot be between the associated limit switch LS1 or LS2 and codereader 14 at the time that the code on a succeeding tray is being read.That is, the distance between limit switch LS2 and code reader I4 ispreferably less than a tray length. This prevents the reading of thesucceeding tray from misdirecting the preceding tray in accordance withsuch reading. If this distance were greater than a tray length, it wouldbe necessary either to space the trays or to use a separate reader foreach branch conveyor. The aforeamasser mentioned spacing of limit switchL32 and code reader 14 from one another ailows control of trays whichare not spaced from one another. After a preceding tray engages limitsswitch L82, which corresponds to limit switch LS1 in FIG. 2, contact llthereof maintains the energizing circuit of relay CR open so that aninput signal from the code reader in response to a succeeding traycannot cause misdirection of the preceding tray.

In the event of power failure, only a tray which has been sensed byreader ld or read but not diverted would be st, that is, the storedsgnel for controlling its destination would be canceled. A tray in anyother position on the conveyor system will, upon restoration of power,be routed to its correct destination. A tray which happened to bebetween reader ld and the limit switch LSlL or LSZ of its destinationbranch conveyor when power fails will, upon restoration of power, travelalong conveyor 2 and enter the last branch conveyor (not shown). In thismanner, the system is adapted to reduce to a minimum the misdirection ofarticles in the event of power failure.

While the systems hereinbefore described are effectively adapted tofulfill the objects stated, it is to be understood that we do not intendto coniine our invention to the particular preferred embodiments of coderesponsive systems disclosed, inasmuch as they are susceptible ofvarious modifications Within departing from the scope of the appendedclaims.

We claim:

l. In a system for identifying and responding to different codes carriedby moving articles to energize electroresponsive load devices:

a code reader mounted at la point adjacent the path of travel of thearticles and having a plurality of sensing means;

one of said sensing means being common to the others and each of theother sensing means forming with said common sensing means a differentcoded combination;

a plurality of switching means each being effective to operate when thecode on an article matches a respective coded combination of sensingmeans;

and a control system comprising a plurality of like control circuitsresponsive to operation of the respective switching means forcontrolling operation of respective electroresponsive load devices;

each said control circuit comprising means responsive to operation ofthe respective switching means for providing lan output signal;

means for storing said output signal until it is utilized;

and means responsive to operation of said storing means for releasingsaid output signal providing means so that it can be reoperated by theswitching means when the code on another `article is read.

2. In a system for identifying and responding to different codes carriedby moving articles to energize electroresponsive loads:

a code reader mounted at a point adjacent the path of travel of thearticles and having a plurality of coded sensing means;

said code reader comprising a plurality of switching means each beingeffective to operate when the code on an` article matches a code sensingmeans; l

and a control system comprising a` plurality of like control circuitsresponsive to operation of the respective switching means to operateelectroresponsive loads; p

each said control system comprising a low voltage amplifier responsiveto operation of said switching means for providing an output signal;

means responsive to s-aid output signal for storing the same;

and means responsive to said article at a predetermined fur-ther pointin its path of travel for utilizing said stored signal to operate saidelectroresponsive load;

l2 i each said ampliiier being provided with input circuit means and agroup of terminals connected to said input circuit means for adaptingsaid ampliiier for operation with either one of two different types ofcode readers one of which is provided with a normally closed switchingdevice normally shunting the input circuit means of the ampliiier torender it ineffective and being operable to unshunt said input circuitmeans when the code on the article matches said coded sensing means torender said amplifier operative to provide an output signal;

and the other type of code reader being provided with a normally openswitching device normally interrupting the input circuit means of theamplifier to render it ineiective and being operable to close said inputcircuit means when the code on the article matches said coded sensingmeans to render said amplifier operative to provide an output signal.

3. ln a system for identifying and responding to different codes carriedby moving articles to energize electroresponsive loads:

a code reader mounted at a point adjacent the path of travel of thearticles and having Ia plurality of coded sensing means;

said code reader comprising a plurality of switching means each beingeffective to operate when the code on an article matches a coded sensingmeans;

and a control system comprising sa plurality of like control circuitsresponsive to operation of the respective switching means to operateelectroresponsive loads;

each said control system comprising a low voltage ampliiier responsiveto operation of said switching means for providing an output signal;

means responsive to said output signal for storing the same;

and means responsive to said article at a predetermined further point inits path of travel for utilizing load stored signal to operate saidelectroresponsive load;

each said amplifier being provided with two input circuits and a groupof terminals connected to said input circuits to adapt said amplifierfor operation with either one of two diiferent types of code readerswhen connected to predetermined input terminals;

one ofsaid code readers being of the type having a normally closedswitching device connectable to rst terminals of said group thereofnormally to shunt a first one of said input circuits to render saidamplifier inelfective and being operable to unshunt said rst inputcircuit when the code on the article matches said coded sensing means torender said ampliiier operative to provide an output signal;

and .the other of said code readers being of the type having a normallyopen switching device connectable to second terminals of said groupthereof normally to interrupt the second input circuit to render saidampliier ineffective and being operable to complete said second inputcircuit when the code on the article matches said coded sensing means torender said amplier operative to provide an output signal.

4. In a conveyor system having va main conveyor for conveying articlestherealong and a plurality of branch conveyors extending from the mainconveyor and diverter devices mounted on the main conveyor at therespective branch conveyor junctions for selectively diverting articlesfrom the main `conveyor onto the branch conveyors, the improvementcomprising a control system for automatically controlling routing ofarticles from the main conveyor .to .the branch conveyors in accordancewith predetermined codes, `said control system comprising a code readerstat-ion mounted at one side of the main conveyor ahead of the branchconveyor junctions, code bearing elements carried by the articles pastsaid code reader station, said code reader station comprising codediscriminating means for detecting and identifying different codes andcomprising a first detecting member for each branch conveyor and asecond detecting member common to said branch conveyors, each rstdetecting member in combination with said common detecting memberforming a 'code discriminating device for a respective branch conveyor,a lpluralty of control circuit-s for the respective branch conveyors,means connecting said code discriminating devices to said controlcircuits whereby each code discriminating device affords an outputcontrol to its associated control circuit in response to identificationof a code on a code bearing element passing thereby, means in each saidcontrol circuit for receiving said output control from the associatedcode discriminating device, means for registering said output controland for restoring said receiving means whereby to retain a recordthereof after the code bearing element has passed by the associated codediscriminating device, a plurality of limit switches one for eachycontrol circuit and mounted on the main conveyor immediately ahead ofeach diverter device for operation by the articles, means in eachcontrol circuit for operating the associated diverter device from anon-diverting position to a diverting position wherein it is effectiveto divert an article from the main conveyor to the associated branchconveyor, and means responsive to operation of one of said limitswitches associated with a control circuit having said record thereinfor controlling the associated diverter device operating means.

5. The invention defined in claim 4, wherein said output controlreceiving means comprises a transistor amplifier having a controlresistor connected across its emitter-base junction, means in said codediscriminating device normally shunting said resistor to maintain saidtransistor non-conducting, and means in said code discriminating meansresponsive to identification of a code for interrupting said shunt torender `said .transistor conducting.

6. The invention defined in claim 4, wherein said out- 14 put controlreceiving means comprises a transistor ampli- Vfier having a controlresistor connected across its emitterbase junction, a source of voltageconnected to said resistor, means in said code discriminating meansnormally interrupting the circuit from said source to said resistor, andmeans responsive to identification of a code for completing said circuitto said resistor to cause current flow through the latter and to rendersaid transistor conducting.

7. The invention defined in `claim 4, wherein the last mentioned meanscomprises means operable concurrently with operation of said diverterdevice for starting the associated branch conveyor running, yand aplurality of limit switches one lfor each branch conveyor and beingmounted ythereon a predetermined distance from the junction thereof withthe main conveyor for operation by the diverted articles to maintainoperation of the associated branch conveyor and to stop the latter whenthe article has disengaged `such limit switch.

8. The invention defined in claim 4, wherein the distances between saidcode reader station and said limit switches are less than the length ofthe articles ibeing conveyed whereby to prevent a succeeding article atsaid code reader station from causing misdirection of a precedingarticle.

References Cited in the file of this patent UNITED STATES PATENTS1,937,303 Worrall Nov. 28, 1933 2,719,629 Robinson Oct. 4, 19552,795,328 Tyler et al. June 11, 1957 2,862,617 Brown Dec. 2, 19582,877,718 Mittag Mar. 17, 1959 2,993,596 Steinbuch I-uly 25, 19613,003,629 Henderson Oct. 10, 1961 3,019,883 Jones Feb. 6, 1962 3,075,653Wales etal Jan. 29, 1963

1. IN A SYSTEM FOR IDENTIFYING AND RESPONDING TO DIFFERENT CODES CARRIEDBY MOVING ARTICLES TO ENERGIZE ELECTRORESPONSIVE LOAD DEVICES: A CODEREADER MOUNTED AT A POINT ADJACENT THE PATH OF TRAVEL OF THE ARTICLESAND HAVING A PLURALITY OF SENSING MEANS; ONE OF SAID SENSING MEANS BEINGCOMMON TO THE OTHERS AND EACH OF THE OTHER SENSING MEANS FORMING WITHSAID COMMON SENSING MEANS A DIFFERENT CODED COMBINATION; A PLURALITY OFSWITCHING MEANS EACH BEING EFFECTIVE TO OPERATE WHEN THE CODE ON ANARTICLE MATCHES A RESPECTIVE CODED COMBINATION OF SENSING MEANS; AND ACONTROL SYSTEM COMPRISING A PLURALITY OF LIKE CONTROL CIRCUITSRESPONSIVE TO OPERATION OF THE RESPECTIVE SWITCHING MEANS FORCONTROLLING OPERATION OF RESPECTIVE ELECTRORESPONSIVE LOAD DEVICES; EACHSAID CONTROL CIRCUIT COMPRISING MEANS RESPONSIVE TO OPERATION OF THERESPECTIVE SWITCHING MEANS FOR PROVIDING AN OUTPUT SIGNAL; MEANS FORSTORING SAID OUTPUT SIGNAL UNTIL IT IS UTILIZED; AND MEANS RESPONSIVE TOOPERATION OF SAID STORING MEANS FOR RELEASING SAID OUTPUT SIGNALPROVIDING MEANS SO THAT IT CAN BE REOPERATED BY THE SWITCHING MEANS WHENTHE CODE ON ANOTHER ARTICLE IS READ.